Questions tagged [mean-variance]
The mean-variance tag has no usage guidance.
27
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Derivation of the tangency (maximum Sharpe Ratio) portfolio in Markowitz Portfolio Theory?
I have seen the following formula for the tangency portfolio in Markowitz portfolio theory but couldn't find a reference for derivation, and failed to derive myself. If expected excess returns of $N$ ...
31
votes
5
answers
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What methods do you use to improve expected return estimates when constructing a portfolio in a mean-variance framework?
One of the main problems when trying to apply mean-variance portfolio optimization in practice is its high input sensitivity. As can be seen in (Chopra, 1993) using historical values to estimate ...
4
votes
1
answer
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Monte Carlo (resampling) in m.v. portfolio optimization
The instability and high sensitivity of optimisation results can be augmented by adding another layer of quantitative methodology in the form of Monte Carlo Simulation. The name Monte Carlo alludes to ...
4
votes
2
answers
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Closed-form analytical solution for the variance of the minimum-variance portfolio?
The portfolio weights vector of the minimum-variance portfolio has a closed-form analytical solution,
$$\boldsymbol{w} = \frac{\boldsymbol{\Sigma}^{-1} \boldsymbol{1} }{\boldsymbol{1}^\top \boldsymbol{...
3
votes
5
answers
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Efficient frontier doesn't look good
Hi I'm trying to draw an efficient frontier. Below is what I used.
returns parameter consists of 9 column returns of portfolio. I selected 10,000 portfolios and this is how my efficient frontier ...
11
votes
2
answers
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Typical risk aversion parameter value for mean-variance optimization?
What are typical values for risk aversion parameters $\lambda$ used in mean-variance optimization? Please provide references.
Just to be clear, I'm talking about the $\lambda$ in $U(w) = w'\mu - \...
9
votes
2
answers
4k
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Comparing MVO with Resampled Efficient Frontier
My question: How can I compare the Resampled Frontier (REF) to the standard MVO frontier when I have been provided with $\mu$, $\Omega$, and don't have access to true future data to test real out of ...
5
votes
2
answers
873
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Contribution of an asset's variance to portfolio variance
How can an asset's variance, $\sigma_i^2$, be shown to contribute to portfolio variance, $\sigma_p^2$?
I was thinking of taking the derivative (first order conditions $\frac{\partial L_{\sigma_p^2}(w,\...
5
votes
1
answer
475
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Quasi Random Monte Carlo in m.v. portfolio optimization
Not specifying a correlation matrix for the Monte Carlo Simulation's random returns is equivalent to assuming no correlation or a correlation coefficient of zero, which will seriously and adversely ...
4
votes
2
answers
501
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What does the concept "standard Markowitz approach" include?
Does "standard Markowitz approach" include only mean-variance approach or does it also include other approach such as minimum-variance approach?
2
votes
2
answers
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Risk contribution of part of a portfolio
Is it quantitatively sound to say that if I have assets $x, y,$ and $z$ in a portfolio, and that the total variance of the portfolio is defined as
$\sigma_p ^2 = w_x^2\sigma_x^2 + w_y^2\sigma_y^2 +...
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1
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Portfolios from Sorts
Some time ago Almgren and Chriss proposed a method for portfolio optimization based on sorting criteria such as $r_1 > r_2 >... > r_N$ instead of explicit expected returns: see
portfolios ...
11
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1
answer
2k
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Minimum Variance and Minimum Tracking Error portfolio as second order cone program
The quadratic optimization (min variance)
$$
w^{T} \Sigma w \rightarrow \text{min},
$$
where $w$ is the vector of portfolio weights and $\Sigma$ is the covariance matrix of asset returns, is a well ...
10
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4
answers
7k
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Markowitz mean-variance optimization as "error maximization"
I hear it said a lot that standard MV optimization "maximizes errors". But I can't find a good explanation for what exactly they mean by this "maximization" of estimation error.
I understand that if ...
8
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3
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6k
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Why does the Markowitz mean-variance model require the assumption of normality?
Given $N$ assets, the Markowitz mean-variance model requires expected returns, expected variances and a $N \times N$ covariance matrix. The joint distribution is fully defined by these measures.
...
6
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1
answer
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Michaud's Resampled Efficient Frontier - Out of Sample Simulation Testing
I will be putting ALL my account points on bounty to whoever answers this question [if your answer is crap but it's the only answer, you're getting the 165 points]. You will have to wait 2 days or so ...
5
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2
answers
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Derivation of portfolio skewness and portfolio kurtosis
Where can I find derivation of formula for portfolio skewness and kurtosis? I can find formulas everywhere, but not their derivations?
For example, the portfolio variance formula, $\sigma_P = w^\top \...
4
votes
1
answer
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Markowitz Mean-Variance Implied Returns
What is the closed form solution for the following inverse Markowitz problem?
Given a mean-variance optimized fully invested portfolio $X$, a risk aversion parameter $\lambda$ and a var-covar ...
3
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2
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1k
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How to perform portfolio optimization with user-defined expected return and variances using R?
I found some functions for Markowitz mean variance portfolio optimization in R such as portfolio.optim in tseries package.
...
3
votes
1
answer
331
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Why does the likelihood of corner solutions in portfolios increase as the number of assets grows?
A three- asset portfolio doesn't seem prone to generating corner solutions, which are very high allocations to one of the assets and $0$ to the others. Instead, when the number of assets is low, these ...
2
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1
answer
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Is quadratic programming used to maximize portfolio skewness and kurtosis?
Quadratic programming, a type of convex optimization, is used to solve the minimum variance portfolio weights $$w = \arg \min_w \sigma_P^2 = w^\top \Sigma w$$
because the objective function coincides ...
2
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2
answers
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Calculating the efficient frontier from expected returns and SD
I'm trying to calculate the efficient frontier (and the optimal portfolio at the Sharpe ratio) given two vectors for a portfolio: (1) expected returns and (2) historical standard deviations. I would ...
2
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2
answers
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Covariance of a GMV portfolio with any asset
Why is that the covariance of a global minimum variance (GMV) portfolio in the efficient frontier with any asset is always the same?
1
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1
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How to implement Konno's Mean-Absolute Deviation Portfolio Optimization Model using LP methods in Excel
Konno proposed a LP method for portfolio optimization using the Mean Absolute Deviation (MAD)
0
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1
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449
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Fixes of quadratic utility when probability of decreasing utility is large
In finance and specifically portfolio theory, a popular utility function is quadratic utility
$$
u(x)=x-\frac{\lambda}{2}(x-\mu_X)^2
$$
where $x$ is wealth and $\lambda$ is the parameter of risk ...
0
votes
2
answers
164
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Why isn't the asset with minimum variance given a 100% portfolio weight? [closed]
The maximum expected return portfolio is the one that assigns a 100% weight to the asset with the highest expected return amongst all assets under consideration.
Shouldn't then the asset with the ...
0
votes
1
answer
360
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Mixed-integer programming approach for index tracking
Suppose you currently own a portfolio of eight stocks. Using the Markowitz model, you computed the optimal mean/variance portfolio. The weights of these two portfolios are shown in the following table:...